Fallow System Research Articles

Soil health benefits of compost persist two decades after single application to winter wheat

AbstractThe effectiveness of frequent compost application in improving soil health is well‐documented. Less is known on the long‐term effects of infrequent compost application to semiarid soils. Compost made of dairy manure and straw bedding was applied once in a dryland organic hard red winter wheat (Triticum aestivum L. emend. Thell.)–fallow system at 50 Mg ha−1 dry wt. in 1994 in a randomized complete block design with three replicates. Twenty‐eight years later, yields in composted plots (1.4 Mg ha−1) remained higher (p < 0.1) than in control plots (0.79 Mg ha−1). Plant‐available P, acid phosphatase activity (ACP), and total N were higher in composted plots by 143%, 37%, and 29%. Soil organic carbon (SOC) and dehydrogenase enzyme activity were greater by 25% and 20% with compost compared to the control, as were aggregate stability determined using SLAKES method, autoclave‐extractable protein, and CO2‐96 h by 143%, 22%, and 16%. Soil extractable K and Zn also increased with compost application. The interaction of ACP and estimated evapotranspiration (ET) emerged as a pivotal factor in explaining the variation in yield. These findings suggest that growers may see some yield improvements from periodic compost applications to dryland organic winter wheat–fallow systems. This strategy could help rebuild SOC and partially counter the challenges of low and variable precipitation.

Soil Microbial Properties of Durum Grown after Camelina, Carinata, Cover Crops, and Fallow

Novel crop rotation is an important factor influencing the composition of soil microorganisms. However, the effect of introducing oilseed and cover crops (CCs) into monoculture durum rotations on soil microbial communities is not clear in the Northern Great Plains. The objective of this study was to evaluate the effects of 2-year durum (Triticum durum D.) rotations with Ethiopian mustard (Brassica carinata A.) or camelina (Camelina sativa L.) or a 10-species forage/CC mix planted to replace fallow rotations with wheat on soil microorganisms. This study was designed as a randomized complete block with three replications in a no-tillage system. The results showed that total bacterial proportion was significantly higher in durum following fallow and camelina compared to durum following CC and carinata. Total fungal proportion was significantly higher in durum following CC compared to durum following oilseed crops and fallow. The fungal-to-bacterial ratio was significantly higher in durum following CC compared to durum following camelina and fallow. The crop species, soil pH and highly variable rainfall influenced the microbial community dynamics. The abundance of specific microbial groups due to crop-related changes might play a key role in the yield of subsequent crops and soil biological health. This study provides valuable insights into the use of CC mix and oilseeds as an alternative crop for fallow in a wheat–fallow system under dryland farming conditions. Future work is required to elucidate the biological mechanisms and functions of the soil microbial communities in the preceding and subsequent crop relative to soil health and crop productivity.

Tillage and cover crops effects on crop yield in wheat double‐cropping systems

AbstractThe United States is experiencing longer crop growing season in most states, which could afford producers the opportunity to diversify into double‐cropping (DC) and cover crop systems rather than the predominant summer and winter fallow systems. Thus, this study evaluated DC and cover crops effects on wheat (Triticum aestivum L.), cotton (Gossypium hirsutum L.), and soybean (Glycine max) yield under conventional tillage (CT) and no‐tillage (NT). Summer cover crops (SCCs) were sunn hemp (Crotolaria juncea L.) and sorghum sudangrass (Sorghum bicolor), while winter cover crops (WCCs) were Austrian winter pea (Pisum sativum) and wheat. Cropping systems were wheat‐fallow (W‐F), wheat‐cotton (W‐C), wheat‐soybean (W‐S), W‐SCC, WCC‐C, F‐C, WCC‐S, and F‐S. Tillage effect on crop yields varied across years. In 2021, wheat yield in CT of W‐C, W‐F, and W‐SCC (2831, 2689, and 2646 kg ha−1) significantly differed from NT of W‐S (1720 kg ha−1). No significant tillage effect was observed on cotton lint yield between W‐C and WCC‐C. For soybean, in 2020, the CT of W‐S and WCC‐S significantly outyielded the NT of W‐S and WCC‐S. Cropping system effect on wheat yield between W‐S and W‐SCC (1419 and 1987 kg ha−1) was significant in 2020 due to low stand counts in W‐SCC arising from the thick SCC biomass. Cotton lint yield in WCC‐C outyielded W‐C in all 3 years but was not significant. Soybean grain yield in W‐S was consistently higher than in WCC‐S, though not significant. Cotton lint and soybean grain yield in the fallow systems were the least. Overall, in a short term, crop yield in DC and cover crop systems were similar.

Biomass and nutrient flow dynamics and sustainability practices to de-risk environmental challenges in the sub-saharan Africa farming system

In sub-Saharan Africa, productivity risks stem from weather variability, while environmental risks include soil nutrient depletion due to unsustainable farming practices that include monoculture, inadequate or lack of soil and water conservation measures, and low-nutrient application. As a result, shifts from the prevailing fallow system to permanent cultivation lead to soil degradation. The present study aimed to quantify the fluxes of biomass, nutrients, and nutrient balances from different fertilizer sources to de-risk the challenges related to agriculture and the environment in Mali. A farm household survey was conducted over two years (July 2018 to June 2020) with 45 households. The survey enabled us to categorize farm households into three typologies: high resource endowment (HRE), medium resource endowment (MRE), and low resource endowment (LRE). Data on sustainability indicators from cropland, livestock, farm input use, and redistribution units enabled the analysis of biomass and nutrient flow dynamics from households to farmlands and vice versa. The nutrient monitoring (NUTMON) tool generated nutrient flows and balances. Results showed that the total annual biomass collected per hectare by HRE (22.3t) is significantly higher than that collected by MRE (13.4t) and LRE (5.35t) farms (P ​< ​0.001). Compared to LRE (10.3 ​t ​ha−1 year−1), HRE and MRE farmers produced six times (60 ​t ​ha−1 year−1) and three times (34 ​t ​ha−1 year−1) more manure, respectively. Farm households with better endowment status observed a higher rate of nutrient utilization. For the major crops, nutrient application rates of HRE farms in kg ha−1 (cotton: 12.6 ​N, 4.2 ​P, 18.2 ​K) and (maize: 9.18 ​N, 2.34 ​P, 10.7 ​K) were significantly higher than that of MRE and LRE farms (P ​< ​0.01). The study confirms that household endowment status determines farmlands' nutrient flows and fertility levels. Quantifying biomass transport and understanding nutrient flow dynamics enable the derivation of context-specific solutions to reduce risks associated with productivity and the environment.

Long‐term 4R nitrogen management in dryland wheat–fallow systems

AbstractSeveral short‐term studies have investigated 4R (right source, rate, time, and place) N management for dryland wheat (Triticum aestivum L.) production and profitability, but few long‐term studies exist in the United States or abroad. This study evaluated long‐term impacts of several aspects of 4R N management on dryland hard red wheat yield, protein, and return to N. Experiments were conducted at Nephi and Blue Creek, UT, during 1995–2007. Fourteen N treatments evaluated performance of starter fertilizer, fall applications of anhydrous ammonia (AA) with and without nitrapyrin (AA‐Nitrapyrin and AA, respectively), and several split applications in the fall and spring. Across years, winter wheat required N to increase yield, protein, and returns at both sites. Applying 56 kg N ha−1 as AA in the fall usually produced the best return to N compared to other N treatments. Starter N (6 kg N ha−1) at fall planting rarely increased yield, protein, or returns at either site. Across both sites, nitrapyrin increased mean annual yield by 0.6 Mg ha−1 and mean return to N by $150 ha−1. Spring application of N was rarely required and only increased yield in 13% of the years. Results indicate that nitrapryin is often needed with fall AA applications to optimize yield and returns and that starter N or extra N in the spring are rarely economical in dryland wheat in Utah and possibly the greater Intermountain West. Further, N rate had the most influence among 4Rs on wheat production and should be the focus of future efforts to improve 4R stewardship.

Influence of agroforestry systems on earthworm diversity and soil properties in a Sudano-Sahelian landscape

Agroforestry systems promote a range of ecological base management to support sustainable agriculture. However, the influence of agroforestry management on soil biodiversity is still poorly investigated in Sudano-Sahelian landscapes. This study aims to guide sustainable management for soil biodiversity conservation in agroforestry systems by determining the drivers of earthworm diversity with their abundance and corresponding soil properties. Nested sampling following three management systems (agroforestry fallow, agroforestry intercropping, agroforestry grazing) and the protected area as a baseline, were designed for data collection in a Sudano-Sahelian landscape. Earthworm inventory and soil sampling (0–10 cm), coupled with a survey focusing on the cropping and fallowing duration with other agricultural practices (herbicide use, soil tillage), were conducted on the farm. The soil analysis included soil texture, bulk density and a suite of chemical analyses (pHKCl, C and N, available macro and micronutrients). The data were analyzed using generalized linear models (GLMs) and ANCOVA to determine the effects of agroforestry systems on earthworm abundance and soil properties. A Principal Component Analysis (PCA) was performed to determine the relationship between the species richness of earthworms, agroforestry systems and soil properties. The results showed a diversity of five species belonging to the endogeic and epigeic ecological groups numbered at 7 ± 3 to 22 ± 10 individuals m−2 (mean ± standard deviation). In agroforestry fallow systems, earthworm diversity and abundance were both highest, and the abundance increased with the fallow duration. The prolongation of cropping duration coupled with herbicide use in agroforestry intercropping systems decreased significantly the abundance of earthworms. Agroforestry grazing systems increased significantly soil C, N and available nutrients, but the abundance of earthworms and species richness were the lowest likely due to soil destructuration by trampling. Overall, soil texture controlled the species richness of earthworms. Fallow management and agricultural practices with fewer herbicide use and soil destructuration, are essential to improve earthworm abundance and diversity.

Can a Crop Rotation and Fallow System Reduce the Carbon Emission Intensity of Agriculture?

Under the carbon emission pattern of “peak carbon and carbon neutrality”, the policy of crop rotation and fallow system (CRFS) is regarded as an important initiative to promote the green, low-carbon, and high-quality development of agriculture. Focusing on balanced panel data from 30 provinces in China from 2010 to 2021, this paper empirically examines the impact of CRFS on agricultural carbon emissions (ACEI) and its internal mechanism using a multi-temporal difference-in-differences model. The benchmark regression results show that CRFS can significantly reduce ACEI, and the results remain robust after validation by multiple methods. Mechanism results show that CRFS is able to reduce ACEI by reducing factor mismatch and promoting the level of agricultural services. Heterogeneity analysis results show that the arable land fallow rotation system is more conducive to promoting the reduction in agricultural carbon emission intensity in the main grain producing areas, main grain marketing areas, high land transfer areas, and plantation areas than in the grain production and marketing balanced areas, low land transfer, and animal husbandry areas. This study demonstrates the effectiveness of the CRFS policy implementation, provides a doctrinal basis for expanding the scope of CRFS implementation, and provides policy recommendations for relevant departments to improve the CRFS policy.

Green manure provides growth benefits for soil mesofauna by promoting soil fertility in agroecosystems

The cultivation of leguminous green manure (LGM) crops in place of bare fallow in summer enhances soil fertility, which can positively impact soil life in the agroecosystem. An improvement in soil life, in turn, can promote soil fertility and agricultural sustainability. Based on an ongoing field trial in the Loess Plateau, China, we investigated the long-term effects of LGM crops and nitrogen (N) fertilization on soil mesofaunal community and analyzed the interrelationships among the various mesofaunal groups and soil fertility under dryland conditions. The results showed that the long-term growth of the LGM crops significantly increased the soil fertility and the abundance, richness, and diversity of the soil mesofaunal community compared to the fallow system. A total of 14 mesofaunal groups were identified only in the LGM system, mainly due to the high root biomass of the LGM crops. Among the three tested LGM crops, soybean and Huai bean performed better than mung bean in providing growth benefits and stable abiotic environments for the soil mesofaunal community. In addition, the long-term application of N fertilizer had an overall negative effect on the soil mesofaunal community under dryland conditions. Moreover, the abundance, richness, and diversity of the soil mesofaunal community were strongly correlated with soil fertility indicators. Hence, the analysis of the soil mesofaunal community can be used as a bioindicator of soil fertility in agroecosystems. The long-term growth of the LGM crops instead of bare fallow efficiently built a more sustainable and fertile soil in the agricultural ecosystem, thus providing a theoretical basis and guiding field management strategies for the development of sustainable agriculture in local and other similar dryland regions.

Impact of bare fallow management on soil carbon storage and aggregates across a rock fragment gradient

AbstractBackgroundOur understanding of C storage in soils lacks insights investigating organic matter (OM) depletion, often studied in bare fallow systems. The content of coarse rock fragments is often excluded, whereas it may affect C storage.AimsWe aim to contribute to a better understanding of the impact of bare fallow on C storage mechanisms in the soil as influenced by its coarse rock fragment contents. We investigated whether bare fallow induced a depletion of C in OM fractions and analyzed to which extent this affected soil aggregate size distribution and the C loading of the clay‐sized fraction.MethodsA comparison of 14 years bare fallow management with adjacent cropped soils located in Selhausen (Germany) provided a gradient of coarse rock fragments of 34%–71%, from which sites with three different fine earth (FE) contents were compared. Across the FE gradient, we isolated particulate OM and mineral‐associated OM fractions, obtained microaggregate and macroaggregate size fractions, and quantified the C loading.ResultsBare fallow management induced an OM depletion at lower contents of FE. There, the management influence was more concentrated onto less FE volume. The contribution of both particulate and mineral‐associated OM fractions to the C in the low‐FE soils decreased. The C loading increased under bare fallow, compared to cropped soil. In the low‐FE soil, we also found less macroaggregates, whereas the C content decreased in some microaggregate size fractions.ConclusionsA high content of coarse rock fragments can enhance OM depletion decreasing mineral‐associated and particulate C under bare fallow.

Public Policies Shaping Mexican Small Farmer Practices and Environmental Conservation: The Impacts of 28 Years of PROCAMPO (1994–2022) in the Yucatán Peninsula

Conditional cash transfer (CCT) programs, generally viewed as policies to modernize and increase agricultural production and commercialization, also have social and environmental impacts. Among the first Mexican CCT programs, PROCAMPO is directed toward traditional agriculture and pays farmers for permanent cultivation, ignoring traditional fallow systems. It was implemented nationally in 1994 to counteract the effects of trade liberalization. Its objectives encompassed modernizing and improving agricultural competitiveness and environmental conservation. Here, we analyze PROCAMPO from the perspective of environmental conservation to understand its effects on agricultural practices and forest cover, specifically in the Yucatán Peninsula, where agriculture sustainability was previously achieved via an alternating cycle of multi-crop system (milpa) and forest. We performed an in-depth program analysis, reviewing 51 documents, including scientific literature, technical evaluations, and official records. Research consistently showed direct effects of PROCAMPO on agricultural practices resulting in extensive land use change, including a reduction in crop diversity and the elimination of traditional milpas and fallow. PROCAMPO has impacted conservation by causing high rates of deforestation. Our findings show the need to reorient the design and implementation of agricultural policy to increase agroecosystem resilience and ecological service provision to face climate change.

Physicochemical Properties of Long-term Rice-fallow Cultivation and Uncultivated Soils of Nalbari, Assam, India

We aimed to assess the changes in physical and chemical properties of soils due to long-term continuous cultivation of rice under a rice –fallow system and that was compared with adjacent uncultivated soils. Soil samples were collected from respective sites and some soil physical (bulk density; BD, water holding capacity; WHC, and moisture content; MC) and chemical properties (pH, electrical conductivity; EC, organic carbon; OC, available N, available P, available K, exchangeable Ca, exchangeable Mg, available S, available Zn and available B) analyzed were evaluated using descriptive statistics. The results indicated that the soils under cultivation with rice- fallow were significantly (P&lt;0.05) higher in BD (1.40 Mg m-3) and lower in WHC (41.34%) than the adjacent uncultivated soils (BD=1.34 Mg m-3 &amp; WHC=42.26%). Soil’s chemical properties were significantly (P&lt;0.05) lower in cultivated rice-fallow soils than the uncultivated soils (pH=5.51 and 5.93, OC=0.63 and 0.89%, available N=245.56 and 418.37 kg ha-1, available P= 31.27 and 42.62 kg ha-1, available K=120.98 and 145.90 kg ha-1, exchangeable Ca=5.35 and 5.93 C mol (p+) kg-1, available S=53.42 and 61.14 kg ha-1, available Zn=0.31 and 0.39 mg kg-1 and available B=0.41 and 0.48 mg kg-1) respectively. Continuous cultivation of crops without adopting proper management practices leads to decline in soil physical and chemical properties and proper management practices have to be adopted to sustain the properties of soil and crop productivity.

Comparison of water-saving potential of fallow and crop change with high water-use winter-wheat – summer-maize rotation

A land fallow system (LFS) designed to adjust the winter-wheat summer-maize cropping system to fallow summer-maize was introduced in Hebei Province to alleviate groundwater depletion in the region. However, some of the water saved was lost through evaporation from bare soil and transpiration by weeds. So far, no measurement has been done in the region to address this non-productive water loss, thereby limiting the water-saving potential of the introduced LFS. Furthermore, the reduction in crop production under the summer-maize – fallow system threatens food security. The objective of this study was to determine which practice is effective to keep soil water during fallow and the exact water-saving potential of different cropping system in the region. Firstly, field experiments were conducted under various soil surface management systems — including plastic mulching (PM), straw mulching (SM), shallow tillage (ST) and weed control (WC). The effects of saving water, controlling weeds and managing nutrients were analyzed under the various surface soil management methods. The results showed that compared with the control (no soil surface management, CK), 177, 64.7, 71.0 and 25.0 mm of water was saved respectively under PM, SM, WC and ST surface soil management methods in 2019–2020. The effect of weed control decreased in the order of PM > WC > SM > ST. While PM significantly increased soil nutrient in all the treatments, the others showed slight but insignificant increases. Secondly, the precise water-use of each of the cropping systems was determined using large lysimeters. The analysis showed that compared with the wheat-maize system, 60–100 mm of water was saved under alternating wheat-soybean, wheat-millet, mung bean – fresh edible maize, spring sweet potato cropping systems. The results were key for technical guide in developing future cultivation adjustment policies.

Low-cost agroforestry technologies for climate change mitigation and adaptation in Sub-Saharan Africa: A review

Agroforestry encompasses a large set of techniques and practices that have the potential to improve farm productivity with minimum environmental impacts in the context of climate change mitigation and adaptation (CCMA). In this paper, we discuss the relevance of agroforestry technologies and practices for CCMA in Sub-Saharan Africa (SSA). We recorded 173 scholarly works and and reviewed 62. Our findings indicate that comprehensive and well-developed technologies are used in agroforestry systems in SSA. They can be classified into four main groups (intercropping, improved fallows, mulching and parkland) and seven sub-groups (relay cropping, hedgerow intercropping, rotational woodlots, coppicing fallows, farmer-managed regeneration, on-farm tree domestication through poly-propagation and mulching) based on factors including the origins and uses of the trees and the types of tree-crop association. Our review showed that the maximum positive effect of parkland agroforestry is obtained when tree density ranges from 20 to 40 tree/ha, indicating an increase in crop production of 915.9 kg/ha. Furthermore, overall, the returns to labour of techniques involving fertilizer trees outperform those for natural fallows by 17%. Agroforestry techniques contribute substantially to the REDD+ program, but the best techniques with the highest cost-benefit- ratio and a substantial CCMA effect appear to be the intercropping and improved fallow systems. However, we observed a lack of detailed context-specific economic, social and environmental costs for the different techniques. For effective and rational decision-making by farmers in their adoption of agroforestry, further research should focus on filling in the detailed economic, social and environmental costs of each technology in each specific context.

ON THE COMPARATIVE ANALYSIS OF THE COMPOSITION OF LYSIMETRIC WATER UNDER CONDITIONS OF DIFFERENT SOIL TREATMENT AND UNDER PHYTOCENOSES

A comparative analysis of the composition of lysimetric waters for 2021–2022 was carried out. for two groups of stationary soil lysimeters in the city. The first group of lysimeters is formed by the system: fallow — grass phytocenosis — overgrown fallow — spruce forest — mixed and broadleaved plantation, developing on the same type of mantle loam. The second group of lysimeters represents soils with different types of tillage: conventional plowing, extradeep planting according to Bushinsky, plowing according to Mosolov, deep plowing according to Kachinsky.For both groups, the same type of migration of components is shown, in which the most migrating elements are carbon, mono- and divalent cations, and chloride ion, with minimal migration of iron, manganese, and aluminum.In the group of lysimeters under various types of vegetation, as the tree canopy develops and, accordingly, the intensity of the biological cycle increases in migrating waters, the concentration of such important biophilic elements as magnesium, calcium, potassium, and carbon increases significantly, and among anions, chloride and sulfate ions. This determines, within the framework of the cluster analysis, two different subgroups in terms of the composition of natural waters: the first one is formed by the fallow-grass phytocenosis — overgrown fallow system, and the second one combines tree plantations.In the group of lysimeters with different tillage, a cluster characterizes the composition of water in lysimeters with reclamation plowing according to Mosolov and deep plowing according to Kachinsky. At the same time, individual aggregates form lysimeters with conventional plowing and ultradeep planting according to Bushinsky. This is explained by the fact that in this group of lysimeters, the initially created soil profile design is transformed, which is characterized by the placement of eluvial and illuvial soil horizons in various combinations and at different depths depending on the type of plowing.

Herbicide Resistance in Summer Annual Weeds of Australia’s Northern Grains Region

For more than two decades, glyphosate has been relied on to control summer annual weeds in fallow systems in Australia’s northern grains region. With numerous cases of glyphosate resistance reported in weed species collected from this region, there are concerns about the future viability of this herbicide. A random seed collection survey of summer weeds was conducted between 2016 and 2018 with the aim of determining the frequency and distribution of resistance to glyphosate and other herbicides commonly used for summer weed control. Glyphosate resistance was ubiquitous in fleabane, with all collected populations resistant to this herbicide. Glyphosate resistance was also prevalent in feathertop Rhodes grass, windmill grass, and awnless barnyard grass, with resistance detected in 68%, 58%, and 36% of populations, respectively. Only 14% of sowthistle populations collected between 2013 and 2108 were resistant to glyphosate. Resistance to haloxyfop was detected in feathertop Rhodes grass, albeit at a low frequency (2%). Other herbicides, such as 2,4-D amine, propaquizafop, and clethodim, provided good control of the broadleaf and grass weeds tested. The results from these surveys conducted between 2013 and 2017 provide a first glimpse of the state of herbicide resistance in key crop weeds for Queensland and the northern region of New South Wales. It is clear that farmers and agronomists need to consider incorporating non-chemical weed management tactics to promote the sustainability of current herbicides.

Assessment of Economic Sustainability of Cropping Systems in the Salt–Affected Coastal Zone of West Bengal, India

Identifying productive, profitable, and less risky cropping systems is pivotal for ensuring sustainable farm–based livelihoods in the context of climatic uncertainties and market volatility, particularly in many developing nations. Conventional field crop research often identifies the best or optimal solutions based on treatment replicates at a specific point in time without considering the influence of market volatility and climatic uncertainties. To address this gap, we conducted an assessment of productivity profitability and climate– and market–uncertainty-driven risk for eleven different rice-based cropping systems (eight existing and three potential systems) in the coastal region of Gosaba Block, West Bengal, India. Farmers’ observations of the best, typical, and worst seasonal yields and price data for the selected cropping systems over the last five to seven years were collected from fifty farm households. Irrespective of the scenarios, the rice–lathyrus systems, followed by rice–onion and rice–lentil systems, recorded the lowest rice equivalent yields and system yields. However, the highest rice equivalent yields and system yields were recorded for rice–chilli systems, followed by rice–tomato and rice–potato–green-gram systems. Per hectare, total paid–out cost (TPC) of rice–tomato systems was higher, followed by rice–chilli, rice–potato–green–gram, and rice–potato systems. However, irrespective of seasonal conditions (best, normal, and worst), rice–chilli systems gave a higher net return followed by rice–tomato and rice–potato–green–gram systems. The rice–fallow system recorded the lowest value for both parameters. Under the worst seasonal conditions, the rice–onion system gave a negative net return. Under all the scenarios, the rice–chilli system gave the highest benefit over cost, followed by the rice–tomato, rice–potato–green-gram, and rice–potato systems. The cumulative probability distribution (CDF) of per ha net income of the rice–tomato system showed first–degree stochastic dominance over other systems, implying that the system is economically the most profitable and less risky. Additionally, the CDF of net income per ha of the rice–chilli system showed second–degree stochastic dominance over the rest of the systems, indicating that the system is economically more profitable and less risky than other rice/non–rice cropping systems except for the rice–tomato system. Furthermore, the risk analysis results suggest that the likelihood of obtaining negative net income was nil for the selected cropping systems, except the rice–onion system had a slight chance (&lt;1%) of providing a negative net return. Considering the productivity and economic viability (e.g., profitability and risk) of different rice–based systems, it is recommended to promote the adoption of the rice–vegetable systems, especially rice–tomato and rice–chilli from among the existing systems and rice–potato–green-gram systems from among the potential systems, for achieving sustainable intensification in these coastal saline tracts of the region.

The Effect of Ornamental Groundcover Habit and Irrigation Delivery on Dynamic Soil Conditions

Sustainable landscapes provide environmental, social, and financial benefits, with interest and adoption increasing due to environmental awareness. Ornamental ground-cover systems have garnered interest in the landscape due to the reduced need for water, fertilizers, pesticides, and maintenance compared to typical landscapes; however, limited research on groundcover ability to modulate soil conditions or suppress weeds exists. This study explored how ornamental groundcover systems impact the sustainability of landscapes. The effects of ground-cover growth habit (matting; bunching) and irrigation delivery method (micro spray; overhead) on soil temperature, volumetric water content (VWC), and electric conductivity (EC), along with impacts on weed growth, soil microbial communities, and plant coverage, were measured. Soil temperatures were generally lower under groundcover species with a matting growth habit, and to a lesser extent, bunching growth habits, in comparison to the warmer fallow systems. Groundcovers with a matting form led to lower VWC values compared to taxa with other growth habits, particularly when micro-irrigated. Plant form did not significantly influence EC values; however, micro spray irrigated plots had significantly higher EC values, likely attributed to irrigation spray patterns. Micro spray irrigation in tandem with matting growth habit taxa decreased weed density more effectively than taxa with bunching growth habits or groundcovers maintained under overhead irrigation. Selection of groundcover species with greater foliar coverage along with implementing more efficient irrigation practices can decrease soil temperatures, soil moisture, and weed density. Incorporating groundcovers in the landscape can decrease maintenance requirements and water/chemical use, thus increasing sustainability and decreasing environmental consequences.

Performance of Linseed (Linum usitatissimum L.) Varieties in Foothills of Nagaland under Irrigated Condition

Background: Linseed, being a short duration crop, can be introduced in rice fallow system in order to derive more benefits. Timely and adequate amount of water to the crop in best possible way helps in optimizing agricultural production. At the same time, the need to meet increasing demand for food will require increased production per unit of water. However, the scope of linseed cultivation is very limited in Nagaland. The farmers of the region are not well-acquainted with linseed cultivation and information on varietal performance of linseeds in Nagaland condition is scanty. Methods: The experiment was laid out in randomized block design with three replications and consisted of seven linseed varieties viz., JLS-95, RLC-153, LSL-93, T-397, Shekhar, Priyam and Parvati. Result: Among all the varieties, JLS-95 produced higher growth attributes viz., plant height (cm), number of leaves plant-1, number of branches plant-1, plant dry matter (g plant-1), crop growth rate (g m-2 day-1) and yield attributes viz., number of capsules plant-1, seed yield (kg ha-1) and stover yield as well was statistically superior in variety JLS-95 over the other varieties.

Preliminary experimental data on surface runoff and soil loss in the Caatinga

AbstractSemi‐arid regions are naturally sensitive to soil erosion due to sparse vegetation cover and concentrated rainfall regime. Absence of conservative practices increases soil loss and reduces water retention. Despite the propagation of erosive process in the Brazilian semi‐arid region, few studies address the spatial and temporal distribution of surface erosive processes. Therefore, the present study presents preliminary results of a monitored soil loss and runoff experiment in the Brazilian semi‐arid region. Four plots were set up on the dominant soil groups, Luvisols and Regosols, traditional land uses, fallow system and cactus palm cultivation. Precipitation, surface runoff and soil loss were monitored for 22 months. The plots with the fallow system were more efficient in containing the hydro‐erosive dynamics than the plots with the cactus palm. The high difference in soil erosion between fallow system plots and cactus palm indicates that the human impact on soil loss is substantial. The significant correlation between precipitation and surface runoff allows the prediction of surface runoff. The weak correlation between precipitation and soil loss indicates that erosion is complex, with a strong influence on soil properties and use. The propagation of erosive processes in the Brazilian semi‐arid region induces loss of soil fertility, acceleration of the desertification process and impoverishment of rural communities. Specific conservative practices should be developed to reduce soil loss and mitigate anthropic disturbance in these areas. The surface runoff in Luvisol was up to 47% higher than those measured in Regosol. The plots with cactus palm showed a loss of organic carbon and nitrogen up to seven times greater than the plots in fallow system. Regosol is more sensitive to land‐use change compared with Luvisol.

Drivers of growth and establishment of the invasive plant Rumex acetosella within Andean fallow systems

Intensification of crop rotations and associated agricultural practices are reducing the capacity of traditional fallows to restore soil fertility and provide forage in Andean cropping systems. While the implementation of improved fallows offers great promise to enhance forage provision and maintain soil productivity, effects of these practices on the establishment of problematic weeds, including non-native plant species, remain poorly understood. To address this knowledge gap, we studied: i) how biotic and abiotic environmental factors influence the establishment and productivity of weeds in traditional fallows; and ii) to what extent improved fallows can help control weedy vegetation in smallholder rotations of the high Andes. Specifically, in this research, we focused on the invasive plant species Rumex acetosella L., which is a common concern of farmers throughout the central Peruvian Andes. We leveraged a multi-site, participatory research trial established in 2017 across eight communities in the region to understand the main drivers of R. acetosella presence and productivity. We used a total of 82 sites, each with paired treatments of traditional fallow (control with natural revegetation) and improved fallow (seeded with Vicia sativa L. and Avena sativa L.). Prior to treatment establishment we measured soil texture, pH, soil organic matter content as well as exchangeable macro-nutrients. Vegetation data was recorded in each treatment and divided into four categories: 1) A. sativa, 2) V. sativa, 3) R. acetosella, and 4) other weeds, and weighed to determine the relative biomass contribution of each. From these data, we calculated an index for R. acetosella pressure, weed pressure, and forage productivity. Our findings indicate that improved fallows greatly suppress weedy vegetation relative to unmanaged controls, including the invasive R. acetosella. Multivariate analyses suggested that R. acetosella abundance was associated with the presence of other non-planted weeds and predictors of soil fertility. The mean R. acetosella index in improved fallows was significantly lower compared to traditional fallows. We found R. acetosella biomass to be greater at lower productivity sites, i.e., those at higher elevations with cooler climates and sites with less fertile soils. Our findings indicate that if the fallow portion of a rotation is kept productive via adequate soil fertility inputs, the biomass of weeds, including the alien R. acetosella, is dramatically reduced.